In a first patent document, there is described a technique in which, in an internal combustion engine provided with a first fuel injection valve for injecting fuel into a cylinder, and a second fuel injection valve for injecting fuel into an intake port, the charging efficiency of intake air is enhanced by making higher an injection ratio of the first fuel injection valve with respect to the second fuel injection valve, when the engine speed is low.
In a second patent document, there is described a technique in which, in an internal combustion engine provided with a fuel injection valve for injecting fuel into a cylinder, intake air in the cylinder is cooled by decreasing an amount of fuel injected from the fuel injection valve per unit time.
In a third patent document, there is described a technique in which, in an internal combustion engine provided with a fuel injection valve for injecting fuel into a cylinder and an EGR mechanism, an injection rate of the fuel injection valve is detected, and a target EGR rate is corrected based on the injection rate thus detected.